str1="hello"
str2='hello'
str3='''hello
world'''
print(str1)
print(str2)
print(str3)
print('he\'lo world') #\转义符
# print('123---{0}---{1}---{2}'.format(4))
str1='hello'

print(f'123---{str1}')
for i in range(1,101,2):
    print("========开始下载=======")
    if i==100:
        print("下载完成")
    else:
        # print(f'{i}%','[',"*"*(i//2),"."*((100-i)//2),']')
        str4="*"*(i//2)+"."*((100-i)//2)
        print(f'{i}%[{str4}]')
print()
